FOUR people including a police officer and the suspect have been killed in a mass shooting at a hospital in Chicago.
The horrifying incident occurred at Mercy Hospital on the US city's South Side at around 3pm local time (9pm GMT) on Monday.
The gunman opened fire on his ex-partner, 38-year-old Dr Tamara O'Neal, in the car park outside before entering the hospital and shooting dead a newly-graduated pharmacist, 25-year-old Dayna Less.
A police officer who responded to the incident, 28-year-old Samuel Jimenez, was also killed inside the building.
#ChicagoPolice Officer Samuel Jimenez died a hero today. He was killed doing what cops do — running into the danger to save others. Sending our condolences and prayers to Officer Jimenez’s family and everyone at @Chicago_Police. #NeverForget pic.twitter.com/Uv4Zkr7Cg2
— Chief Terence Monahan (@NYPDChiefofDept) 20 November 2018
According to reports in the US, the shooter – 32-year-old Juan Lopez – also died at the scene, but it is unclear whether he was killed by police or turned his gun on himself.
Mayor of Chicago Rahm Emanuel said the attack "tears at the soul of our city".
He added: "The city of Chicago lost a doctor, pharmaceutical assistant and a police officer, all going about their day, all doing what they loved.
"It is the face and a consequence of evil."
— Charlie De Mar (@CharlieDeMar) 20 November 2018
Dr O'Neal was an emergency physician at the 292-bed hospital and was reportedly the gunman's former fiancée.
Police said the pair were arguing outside the hospital before Lopez "lifted up his shirt and displayed a handgun" when a friend tried to intervene.
Gunfire broke out as the friend ran for help, before Lopez "stood over" Dr O'Neal and "shot her three more times", Chicago Police Superintendent Eddie Johnson said.
This is Dayna Less. She lost her life at the hands of a crazed madman at Mercy Hospital. Such a sad day in the city. pic.twitter.com/OM45N1HTCK
— Mark in Chicago (@Smackoff25Champ) 20 November 2018
He then ran into the hospital shooting at random and killed Ms Less, who was getting off an escalator at the time.
Police Officer Jimenez was killed in an exchange of fire with Lopez inside the hospital.
A second policeman miraculously avoided injury after a bullet fired in his direction struck his firearm.
Lopez – who had been set to marry Dr O'Neal on October 27 before they split up – died in as yet unclear circumstances moments later.
Shots were fired at a 2nd CPD officer in the Mercy Hospital Shooting, but he wasn't injured. Instead, the bullet struck his holster and embedded itself in his gun: https://t.co/hVPwgbrkXv pic.twitter.com/OvMI0ln3l6
— ABC 7 Chicago (@ABC7Chicago) 20 November 2018
Dr Patrick Connor, director of the Mercy Hospital's emergency department, said Dr O'Neal was "dedicated to caring for her community – a wonderful individual".
Officer Jimenez was a married father-of-three. "We cannot thank him enough for his courage and bravery today," Dr Connor said.
Nearby buildings, including the National Teachers Academy, were put on lock-down during the attack.
Mercy Hospital later tweeted that all of its patients were safe.